The present invention relates, in general, to a brake cylinder piston travel indicator and, more particularly, to a brake beam mounted brake cylinder piston travel indicator which is located in an easily viewable location for readily determining piston travel in truss-type railway vehicle brake assemblies.
Freight trains typically undergo a pre-departure terminal test in which the air brake equipment of each car is inspected prior to the train being cleared to proceed from the train make-up yard. This inspection requires a trainman to xe2x80x9cwalk the trainxe2x80x9d visually checking each car s brake equipment. Prior art type truck mounted brake assemblies include a piston travel indicator attached to the brake cylinder assembly for monitoring piston travel to determine whether or not the brake equipment is functioning properly.
The currently used piston travel indicator comprises an indicating means, such as a flag, which moves along a measuring means. This measuring means has an acceptable operating range or zone marked thereon. The inspector views the location of the flag with respect to the acceptable operating range to determine whether or not the braking equipment is functioning properly. For example, if the flag is below the range, then such would indicate that the slack adjuster trigger needs to be adjusted. If, on the other hand, the flag is above the range, such could indicate that either the slack adjuster is out of capacity and the brake shoes are too worn, or the slack adjuster is not functioning properly and requires maintenance.
Due to the location of this piston travel indicator within the truck mounted brake assembly underneath the car, it is often difficult for the trainman to readily view the indicator and to make a proper determination as to the functioning of the braking equipment. It thus becomes burdensome to inspect the braking equipment of the train and consequently more time consuming to complete the terminal test.
It is an object of the present invention to provide a brake cylinder piston travel indicator which is located in a readily viewable location for determining the amount of travel of a fluid activated piston.
It is a further object of the invention to provide a brake cylinder piston travel indicator which may be readily viewed by train inspection personnel so that such personnel may make a proper determination regarding the functioning of the train s braking equipment.
It is another object of the invention to position this brake cylinder piston travel indicator in a location on each braking assembly and/or on one or both sides of the railway vehicle so that train inspection personnel may quickly perform a pre-departure terminal test.
It is yet another object of the invention to provide a brake cylinder piston travel indicator which may be mounted onto braking systems currently in use and is particularly applicable to truss-type brake assembly systems.
In addition to the objects and advantages listed above, various other objects and advantages of the invention will become more readily apparent to persons skilled in the relevant art from a reading of the detailed description section of this document. The other objects and advantages will become particularly apparent when the detailed description is considered along with the drawings and claims presented herein.
Briefly, and in accordance with the forgoing objects, the invention comprises a brake cylinder piston travel indicator for monitoring an amount of piston travel in a brake cylinder assembly in a railway braking system. The railway braking system includes a brake beam and a brake cylinder piston within the brake cylinder assembly which is in engagement with an end of a brake cylinder force transfer lever. The brake cylinder piston travel indicator of the invention comprises a rod member which is rotatably secured to and extends substantially parallel with at least a portion of the brake beam. A means is provided which associates or operationally interconnects the rod member with the cylinder force transfer lever and is capable of transferring a rotational force to the rod member. This rotational force is caused by activation of the piston in the brake cylinder assembly. At least one indicating means is provided which is engagable with a first end of the rod member and is capable of responding to the rotation of the rod member and indicating an amount of travel of the piston during activation thereof in the brake cylinder assembly.